US1463152A - Electbolytic condenser - Google Patents

Description

Patented July 31, 1923.

UNITED STATES PATENT OFFICE.

LEWIS W. CHUIBB, OF P I'ITSBURGH, PENNSYLVANIA, ASSIGIIOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATIONOF PENNSYLVANIA ELECTROLYTIC CONDENSER.

Application filed December 30, 1919. Serial No. 348,444.

To all whom it may concern-7 Bef'it known that I, LEWIS W. CHUBB, a citizen of the United States, and a resident of Pittsburgh, in the county of 'Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Electrolytic Condensers, of which the following is a s ecification.

y invention relates to electrolytic condenscrs and it has, for its primary object, the construction of condensers which shall provide satisfactory power-factor correction under continuous operating conditions.

It is well known to those familiar with the art that condensers, of the type formed by employing a plurality'of fi plates immersed in a suitable electrolyte, connected in 'a powensupply circuit; for power-factor correction, or for other purposes, tend to become unstable and operate with an increased power factor or with increased losses. This unstable conditionobtains when the volta e impressed upon one of the electrodes is slightly higher than on the other, which causes the-electrode having the higher impressed volt e'tovhave less capacitance than the othe his'unbalanced condition-becomes aggravated and, if it i's not relieved in some mannergthe condenser electrode having the lower capacitance increases to the break-down voltage and produces high losses occasioned by the anode leakage, or sparkling.

One object-of my invention, thereiore,re-

- sides in the provision of apparatus that shall insure satisfactory operating conditions in a condenser which is continuously connected in a power circuit.

, Another object of my invention is to provide apparatus, which may be employed in conjunction with an electrolytic condenser to insure good operating characteristics, which shall be relatively inexpensive, simple in construction and easil repaired With these and other objects in view, my invention will be more fully described, illustrated in the drawin in the several iews of which correspon ing numerals indicate like parts, and then particularly pointed out in the claims.

In the drawings, Fig. 1 is a diagrammatic view of an electrolytic condenser having a -forming convenientto have. them readilyinspe'cte'd to insure satisfactory operation. In practicing my invention, therefore, I provide apparatus for insuring-stableoperation of an electrolytic condenser which may be connec ted' in a power circuit andjnot subject to inspection exceptat convenient, and perhaps mfrequent intervals. I ma employ a dynamometer type of relay whi is operated by'a diiference in potential betweenthe main gelectrodes, The relay automatically connects an auxiliary electrode of relatively low; capacitance; on'e ofjthemain electrodes fwh chffis ofhigher' potential than the other toi'threby increase, the capacitance-of the electrodehaving the highr'potential' and thereby" cause its potential to be reduced to that of the other electrode.

To insure a clear understanding of my invention, I have shown, in Fig. 1,. an electrolytic condenser, 1 oompris' a tank 2 containin anelec'trolyte 3,in viich aplurality of mam electrode's'd and 5' areimmersed. The main electrodes 4 and 5 are co f l ected to a secondary winding 6 of a' transformer or to a balancing impedance device. I prefer to'e'mp'loy a. dynamo meter ty of relay]? which comprises a core mem er 8 having a winding 9 surrounding a portion of the core and connected in serieswith a' non-inductive resistor 9 and across the supply circuit, or in parallel relation to the secondary winding 6, as indicated at 10 and 11. A rotatable armature member 12 is mounted upon ashaft 13, upon which acontact arm 14 is ri idly mounted and is adapted to engage either of a plurality of contact members 15 and 16 which.are connected to the electrodes 4 and 5', respectively. The

frequently located in places where it, is inarmature 12 on its shaft 13 is disposed be 1 tween the ends of the core member 8. A current coil 17 is wound about the armature 12 and is connected, at one end, through a condenser 18 and a resistoii-l f to"the midoint'bf the secondary winding 6 and, at its other end, to a small electrode which is immersed-in the electrolyte 3. An auxiliaigy film-forming electrode 21, which is preferably of less area than the main electrodes 4 and 5, is connectedto' the arm 14 direction of the current. through the coil w1'7,ffivhenthearmature 12 is rotated, the arm"1'4iengages one of thecontact members 15"a'nd '16 and. connects the auxiliary electrode '21 to the main electrode having the higher'potehtial: The condenser 18 is conr'lcteii in serieswith the current coil 17 to iejvenc "any fiowjof direct current through t ecbil' 17;"but it, permits of free passage of alternating current when unbalanced volurge conditions obtain. On" account of the fact that thecondenser 18 tends to establish aqiiadrature'current'in the coil 17 and, since themil 9" is' essentially a reactance device 'whichnl'so takes lquadrature current, it is desirable to connect theresistor 19 in series the condenser- 18 to bring the current in the 'eoi l I7 s'ub stantially in phase with the potential difference between the electrol be?) and the mid-point of the winding 61 he resistor 9" in the field circuit keeps the current and field flux in the core 8 substliflitially in time" phase with thefp'otential adrosls the' electrodes 4 and 5! This insures the'fc'omponentfields of the relay device 7 being in time phase and giving the required tor ue.f

enithe total voltage across winding 6 is equally divided between the electrodes 4 and 5, the potential of electrode 20 is the same ast-hat of the midpoint of winding 6 and, therefore, there is'no flow of current through coil 17. When the voltage on one of the electrodes 4 or 5 increases, there arises a difi'erence of potential between the electrode 20 and the midpoint of winding 6, the magnitude and direction of which causes a current to flow in the corresponding direction between the'said points, thus energizing' the coil 17 'and movino' contactor 14'to add electrode area 21 to either of the main electrodes 1 and 5. After a time the voltage between electrodes 4 and 5 becomes equalized and the coil 17 is decncrgized, causing the contactor 14 to more into its neutral position and disconnectingelectrode "21 from the circuit. When the voltage again becomes unbalanced, the cycle is repeated.

It will be appreciated from the foregoing description that any unstable voltage conditions will cause the relay 7 to actuate the lever arm '14 and connect the auxiliary electrode 21 to the main electrode which is having the higher alternating potential impressed thereon. The fluttering relay device will thus keep the voltage balanced by changing the connections of the auxiliary e ectrode from side to, side. The form of relay shown in this instance provides for connection of the total capacity of the auxiliary electrode to the one orthe other of the main electrodes when the voltage is sufiicient- 1y unbalanced. I may provide a progressive compensation for-slight variations in voltage conditions employed a modified form of my in'vention asshownin Fig. 2. As here shown, the a m 1'4i adapted to engage any one of aserie s of taps 22 which are connected to various points on the winding 6. An additional condenser 23 is connected between the auxiliary electrode 2-1 and the arm .14 to reyent the fiow of direct current to the sum iary electrode.

By using a construction, s'uchas shown in Fig. 2, the capacitance of the auxiliary electrode21 is not immediately connected to one electrode or; to the other, as the voltage is varied but is "connected to one of the taps 22 on the sidecf the windin connected to the electrode having the higher voltage. The auxiliary electrode 21 is thus connected to the one or the other of themain electrodes, in a series of steps, by the arm 14 making successive engagement with the various ta s22. Such a construction may be prefera le, insome instances hccause' a more delicate adjustment of voltage balance is maintained. 7

It will be apparent,'form the description of the condensers embodying my invention, that they maybe connected in a power circuit and insure satisfactory operation without constant attention because the .voltage conditions are maintained in balance and, consequently, the capacitances of the condenser electrodes are maintained at substantially an equal value. Furthermore, the condensers will be longer-lived on account of the fact that stable conditions'are maintained. Any corrosive effects on the plates, occasioned by exceptionally high voltages, will be avoided.

'Although I have shown and specifically described a plurality of condensers which embody my invention, it is obvious that slight changes may be made in their construction and in the electrical connections and construction of the relay employed to insure stable operating conditions, and I desire, therefore, that no limitations shall be imposed except such as are indicated in the appended claims.

I claim as my invention l. The combination with an electrolytic condenser comprising a plurality of electrodes immersed in an electrolyte, of means for maintaining the capacitances of the condenser electrodes substantially equal, said means including a switch which is actuated when the voltage is unequally divided between the electrodes.

2. The combination with an electrolytic condenser comprising a plurality of main electrodes immersed in an electrolyte, of means for maintaining the capacitances of the condenser electrodes substantially equal, said means including an auxiliary electrode and means for connecting the auxiliary electrode to a main electrode when the impressed voltage is unequally divided between the main electrodes.

3. The combination with an electrolytic condenser comprising a plurality of main electrodes immersed in an electrolyte, of means for maintaining the capacitances of the condenser electrodes substantially equal, said means including an auxiliary electrode of less area than the main electrodes, and means for connecting the auxiliary electrode to a main electrode when the impressed voltage is unequally divided between the main electrodes.

4. The combination with an electrolytic condenser comprising a plurality of main electrodes and an auxiliary electrode, all immersed in an electrolyte, of means for maintaining the capacitances of the condenser electrodes substantially equal, said means including a lurality of contact members connected to t e main electrodes of the condenser, a contact arm connected to the auxiliary electrodes and adapted to engage either of the contact members, and means for actuating the contact arm, said means being governed by the difi'erence of potential impressed upon the electrodes of the condenser.

5. The combination with an electrolytic condenser comprising a plurality of filmforming electrodes and an auxiliary filmfonning electrode of less area than the other electrodes, all immersed in an electrolyte, of means for maintaining the capacitances of the condenser electrodes substantially equal, said means including a plurality, of contact members connected to the electrodes, a contact arm adapted to engage the contact members and connected to the auxiliary electrode, a movable supporting member for the contact arm, and means for moving the supporting member to cause the contact arm to engage one of the contact members when nected to the main electrodes,

mam electrodes and nected to the contact members,

the voltage impressed upon the main electrodes is unequally divided therebetween.

6. The combination with an electrolytic condenser comprising a plurality of main electrodes and an auxiliary electrode of less area than the other electrodes, of means for maintaining the capacitance of the con denser electrodes substantially equal, said means including an impedance device connected to the main electrodes, a plurality of contact members connected to the impedance device, a contact arm adapted to successively engage the contact members and connected to the auxiliary electrode, and means for moving the contact arm to engage the contact members governed by the difference in alternating potential between the midpoint of the impedance device and the electrolyte.

7. The combination with an electrolytic condenser comprising a plurality of main electrodes and an auxiliary electrode of less area than the other electrodes, of means for maintaining the capacitances of the condenser electrodes substantially equal, said means including an impedance device cona plurality of contact members connected to the impedance device at substantially equally spaced intervals, a contact arm adapted t successively engage the contact members and connected to theauxiliary electrode, a condenser connected in serie with the contact arm and the auxiliary electrode, and means for mov ing the contact arm to successively engage the contact members controlled by the difference 1n alternating potential between the midpoint ofthe impedance device and the electrolyte.

8. In an electrical power system, an electrolytic condenser comprising a plurality of an auxiliary electrode of less area than the main electrodes all immersed in an electrolyte and having the main electrodes connected to an inductive windmg, a plurality of contact members con winding, a contact arm connected to the auxiliary electrode and adapted to make engagement with either of the a rotatable support for the contact arm, an electrical coil disposed about the rotatable support, means for establishing; a magnetic field about the sup port, an means for causing an alternating current to traverse the coil surrounding the support when the voltage impressed upon the main electrodes is unequally divided therebetween, whereby the contact arm is caused to engage one of the contact members to connect the auxiliary electrode to the main electrode havin the higher potential with respect to the e ectrolyte.

In testimony whereof, I have hereunto subscribed my name this 23rd day of December, 1919.

LEWIS W. CHUBB.

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